Don't reset the chpos/byte_pos to 0 in new_parser_from_source_str.

This correctly fixes issue #1362.

chpos/byte_pos are now the offsets within a particular file, but
rather the offsets within a virtual file with is formed by combing all
of the modules within a crate.  Thus, resetting them to 0 causes an
overlap and hence, bogus source locations.

Fix #1362 by moving chpos/byte_pos to parse_sess so that
new_parser_from_source_str has access to them and hence can chose an
initial value that is not already been used in the crate.

Note that the trigger for bug 1361 was that syntax/ext/expand.rs calls
parse_expr_from_source_str (which calls new_parser_from_source_str)
using the same codemap as the current crate (and hence causing overlap
with files in the crate as new_parser_from_source_str resets the
chpos/byte_pos to 0).

7 files changed, 47 insertions, 26 deletions

diff --git a/src/cargo/cargo.rs b/src/cargo/cargo.rs
index a12c01de547..424d930e35c 100644
--- a/src/cargo/cargo.rs
+++ b/src/cargo/cargo.rs
@@ -105,7 +105,9 @@ fn load_pkg(filename: str) -> option::t<pkg> {
     let sess = @{
         cm: cm,
         mutable next_id: 1,
-        diagnostic: diagnostic::mk_handler(cm, none)
+        diagnostic: diagnostic::mk_handler(cm, none),
+        mutable chpos: 0u,
+        mutable byte_pos: 0u
     };
     let c = parser::parse_crate_from_crate_file(filename, [], sess);
 
diff --git a/src/comp/driver/driver.rs b/src/comp/driver/driver.rs
index 9d9c0542c82..9d8d9ac03b7 100644
--- a/src/comp/driver/driver.rs
+++ b/src/comp/driver/driver.rs
@@ -488,7 +488,9 @@ fn build_session(sopts: @session::options, input: str,
       parse_sess: @{
           cm: codemap,
           mutable next_id: 1,
-          diagnostic: diagnostic_handler
+          diagnostic: diagnostic_handler,
+          mutable chpos: 0u,
+          mutable byte_pos: 0u
       },
       codemap: codemap,
       // For a library crate, this is always none
diff --git a/src/comp/syntax/parse/eval.rs b/src/comp/syntax/parse/eval.rs
index 897cfe03e09..ca7af9e273d 100644
--- a/src/comp/syntax/parse/eval.rs
+++ b/src/comp/syntax/parse/eval.rs
@@ -14,8 +14,6 @@ export eval_crate_directives_to_mod;
 type ctx =
     @{p: parser,
       sess: parser::parse_sess,
-      mutable chpos: uint,
-      mutable byte_pos: uint,
       cfg: ast::crate_cfg};
 
 fn eval_crate_directives(cx: ctx, cdirs: [@ast::crate_directive], prefix: str,
@@ -76,12 +74,12 @@ fn parse_companion_mod(cx: ctx, prefix: str, suffix: option::t<str>)
     if file_exists(modpath) {
         #debug("found companion mod");
         let p0 = new_parser_from_file(cx.sess, cx.cfg, modpath,
-                                     cx.chpos, cx.byte_pos, SOURCE_FILE);
+                                     SOURCE_FILE);
         let inner_attrs = parse_inner_attrs_and_next(p0);
         let first_item_outer_attrs = inner_attrs.next;
         let m0 = parse_mod_items(p0, token::EOF, first_item_outer_attrs);
-        cx.chpos = p0.reader.chpos;
-        cx.byte_pos = p0.reader.pos;
+        cx.sess.chpos = p0.reader.chpos;
+        cx.sess.byte_pos = p0.reader.pos;
         ret (m0.view_items, m0.items, inner_attrs.inner);
     } else {
         ret ([], [], []);
@@ -108,8 +106,7 @@ fn eval_crate_directive(cx: ctx, cdir: @ast::crate_directive, prefix: str,
                 file_path
             } else { prefix + std::fs::path_sep() + file_path };
         let p0 =
-            new_parser_from_file(cx.sess, cx.cfg, full_path, cx.chpos,
-                                 cx.byte_pos, SOURCE_FILE);
+            new_parser_from_file(cx.sess, cx.cfg, full_path, SOURCE_FILE);
         let inner_attrs = parse_inner_attrs_and_next(p0);
         let mod_attrs = attrs + inner_attrs.inner;
         let first_item_outer_attrs = inner_attrs.next;
@@ -119,8 +116,8 @@ fn eval_crate_directive(cx: ctx, cdir: @ast::crate_directive, prefix: str,
             syntax::parse::parser::mk_item(p0, cdir.span.lo, cdir.span.hi, id,
                                            ast::item_mod(m0), mod_attrs);
         // Thread defids, chpos and byte_pos through the parsers
-        cx.chpos = p0.reader.chpos;
-        cx.byte_pos = p0.reader.pos;
+        cx.sess.chpos = p0.reader.chpos;
+        cx.sess.byte_pos = p0.reader.pos;
         items += [i];
       }
       ast::cdir_dir_mod(id, cdirs, attrs) {
diff --git a/src/comp/syntax/parse/parser.rs b/src/comp/syntax/parse/parser.rs
index b18db178fcd..cb7e1144334 100644
--- a/src/comp/syntax/parse/parser.rs
+++ b/src/comp/syntax/parse/parser.rs
@@ -25,7 +25,10 @@ enum file_type { CRATE_FILE, SOURCE_FILE, }
 type parse_sess = @{
     cm: codemap::codemap,
     mutable next_id: node_id,
-    diagnostic: diagnostic::handler
+    diagnostic: diagnostic::handler,
+    // these two must be kept up to date
+    mutable chpos: uint,
+    mutable byte_pos: uint
 };
 
 fn next_node_id(sess: parse_sess) -> node_id {
@@ -91,7 +94,7 @@ impl parser for parser {
 }
 
 fn new_parser_from_file(sess: parse_sess, cfg: ast::crate_cfg, path: str,
-                        chpos: uint, byte_pos: uint, ftype: file_type) ->
+                        ftype: file_type) ->
    parser {
     let src = alt io::read_whole_file_str(path) {
       result::ok(src) {
@@ -102,7 +105,7 @@ fn new_parser_from_file(sess: parse_sess, cfg: ast::crate_cfg, path: str,
         sess.diagnostic.fatal(e)
       }
     };
-    let filemap = codemap::new_filemap(path, chpos, byte_pos);
+    let filemap = codemap::new_filemap(path, sess.chpos, sess.byte_pos);
     sess.cm.files += [filemap];
     let itr = @interner::mk(str::hash, str::eq);
     let rdr = lexer::new_reader(sess.cm, sess.diagnostic,
@@ -113,7 +116,7 @@ fn new_parser_from_file(sess: parse_sess, cfg: ast::crate_cfg, path: str,
 fn new_parser_from_source_str(sess: parse_sess, cfg: ast::crate_cfg,
                               name: str, source: str) -> parser {
     let ftype = SOURCE_FILE;
-    let filemap = codemap::new_filemap(name, 0u, 0u);
+    let filemap = codemap::new_filemap(name, sess.chpos, sess.byte_pos);
     sess.cm.files += [filemap];
     let itr = @interner::mk(str::hash, str::eq);
     let rdr = lexer::new_reader(sess.cm, sess.diagnostic,
@@ -2482,21 +2485,30 @@ fn parse_native_view(p: parser) -> [@ast::view_item] {
 
 fn parse_crate_from_source_file(input: str, cfg: ast::crate_cfg,
                                 sess: parse_sess) -> @ast::crate {
-    let p = new_parser_from_file(sess, cfg, input, 0u, 0u, SOURCE_FILE);
-    ret parse_crate_mod(p, cfg);
+    let p = new_parser_from_file(sess, cfg, input, SOURCE_FILE);
+    let r = parse_crate_mod(p, cfg);
+    sess.chpos = p.reader.chpos;
+    sess.byte_pos = p.reader.pos;
+    ret r;
 }
 
 
 fn parse_expr_from_source_str(name: str, source: str, cfg: ast::crate_cfg,
                               sess: parse_sess) -> @ast::expr {
     let p = new_parser_from_source_str(sess, cfg, name, source);
-    ret parse_expr(p);
+    let r = parse_expr(p);
+    sess.chpos = p.reader.chpos;
+    sess.byte_pos = p.reader.pos;
+    ret r;
 }
 
 fn parse_crate_from_source_str(name: str, source: str, cfg: ast::crate_cfg,
                                sess: parse_sess) -> @ast::crate {
     let p = new_parser_from_source_str(sess, cfg, name, source);
-    ret parse_crate_mod(p, cfg);
+    let r = parse_crate_mod(p, cfg);
+    sess.chpos = p.reader.chpos;
+    sess.byte_pos = p.reader.pos;
+    ret r;
 }
 
 // Parses a source module as a crate
@@ -2589,18 +2601,18 @@ fn parse_crate_directives(p: parser, term: token::token,
 
 fn parse_crate_from_crate_file(input: str, cfg: ast::crate_cfg,
                                sess: parse_sess) -> @ast::crate {
-    let p = new_parser_from_file(sess, cfg, input, 0u, 0u, CRATE_FILE);
+    let p = new_parser_from_file(sess, cfg, input, CRATE_FILE);
     let lo = p.span.lo;
     let prefix = std::fs::dirname(p.reader.filemap.name);
     let leading_attrs = parse_inner_attrs_and_next(p);
     let crate_attrs = leading_attrs.inner;
     let first_cdir_attr = leading_attrs.next;
     let cdirs = parse_crate_directives(p, token::EOF, first_cdir_attr);
+    sess.chpos = p.reader.chpos;
+    sess.byte_pos = p.reader.pos;
     let cx =
         @{p: p,
           sess: sess,
-          mutable chpos: p.reader.chpos,
-          mutable byte_pos: p.reader.pos,
           cfg: p.cfg};
     let (companionmod, _) = fs::splitext(fs::basename(input));
     let (m, attrs) = eval::eval_crate_directives_to_mod(
diff --git a/src/fuzzer/fuzzer.rs b/src/fuzzer/fuzzer.rs
index fa6c88787d4..3dbcadb9449 100644
--- a/src/fuzzer/fuzzer.rs
+++ b/src/fuzzer/fuzzer.rs
@@ -419,7 +419,9 @@ fn parse_and_print(code: str) -> str {
     let sess = @{
         cm: cm,
         mutable next_id: 0,
-        diagnostic: diagnostic::mk_handler(cm, none)
+        diagnostic: diagnostic::mk_handler(cm, none),
+        mutable chpos: 0u,
+        mutable byte_pos: 0u
     };
     write_file(filename, code);
     let crate = parser::parse_crate_from_source_str(
@@ -566,7 +568,9 @@ fn check_variants(files: [str], cx: context) {
         let sess = @{
             cm: cm,
             mutable next_id: 0,
-            diagnostic: diagnostic::mk_handler(cm, none)
+            diagnostic: diagnostic::mk_handler(cm, none),
+            mutable chpos: 0u,
+            mutable byte_pos: 0u
         };
         let crate =
             parser::parse_crate_from_source_str(
diff --git a/src/rustdoc/attr_parser.rs b/src/rustdoc/attr_parser.rs
index f952bb1a92f..8074b47ab5b 100644
--- a/src/rustdoc/attr_parser.rs
+++ b/src/rustdoc/attr_parser.rs
@@ -289,7 +289,9 @@ mod test {
         let parse_sess = @{
             cm: cm,
             mutable next_id: 0,
-            diagnostic: diagnostic::mk_handler(cm, none)
+            diagnostic: diagnostic::mk_handler(cm, none),
+            mutable chpos: 0u,
+            mutable byte_pos: 0u
         };
         let parser = parser::new_parser_from_source_str(
             parse_sess, [], "-", source);
diff --git a/src/rustdoc/parse.rs b/src/rustdoc/parse.rs
index 0afc625378d..11eb469e641 100644
--- a/src/rustdoc/parse.rs
+++ b/src/rustdoc/parse.rs
@@ -12,7 +12,9 @@ fn new_parse_sess() -> parser::parse_sess {
     let sess = @{
         cm: cm,
         mutable next_id: 1,
-        diagnostic: diagnostic::mk_handler(cm, none)
+        diagnostic: diagnostic::mk_handler(cm, none),
+        mutable chpos: 0u,
+        mutable byte_pos: 0u
     };
     ret sess;
 }